Around Victorville in CA, there are ‘exits’ that take you right up the face of steep hills. The purpose is to give trucks with failed brakes a way to stop their rigs from barreling down an incline out of control. I took my Cherokee up one to see how far I could get. About at a forty degree angle, I chickened out.
I’ve seen those runaway ramps in other states. Many of them have staggered ramps with level parts so that the trucks don’t have to come to a stop on a grade and roll backwards. Going down grades between 8 and 12 percent, those are vital.